In mobile communications networks, the air interface is the interface between a mobile handset and a base transceiver station. For voice telephone calls, typical air interface protocols use frequency division multiple access (FDMA), code division multiple access (CDMA), or time division multiple access (TDMA) to provide multiple channels between the BTS and the mobile handsets. In GSM networks, a combination of TDMA and FDMA is used.
One problem with conventional mobile communications networks is that the voice and control signals may be weakened inside of structures, such as buildings, due to poor frequency penetration, scattering, fading, or other undesirable signal effects. As a result, when a mobile user desires to use his or her handset within a structure, access to the network will be either impossible or of very poor quality.
WLAN protocols, such as the IEEE 802.11x family of protocols, are increasingly being used to provide broadband Internet access inside of buildings. For example 802.11 access points are commonly used within homes, offices, hotels, airports, and coffee shops to provide wireless broadband Internet access to users inside of the buildings. While WLAN protocols are increasingly being used to provide wireless data access within structures, these protocols are not typically used to provide voice network access, such as mobile voice communications network access, within structures.
Current attempts to use WLAN and air interface protocols in the same equipment utilize WLAN and air interface protocols independently to provide broadband voice and data access. For example, WLAN and GSM transceivers have been used independently to allow private user equipment to connect to a public cellular network and a broadband data connection. However, there is currently no known solution that seamlessly combines WLAN protocols with air interface protocols to provide improved voice communications access to the telephone network.
Accordingly, in light of the shortcomings associated with conventional mobile communications networks and the availability WLAN protocols, there exists a need for improved methods and systems for using WLAN and air interface protocols in combination to provide improved voice communications access to the telephone network.